a) Field of the Invention
The present invention relates to a method of fabricating the rail of a magnetic head capable of improving work precision and production yield, in which the rail surface is etched and/or milled to depths of at least two steps.
b) Description of the Related Art
A flying type magnetic head of a hard disk drive has, for example, the structure shown in FIG. 2. This magnetic head 10 has a negative pressure slider 11 whose top surface 14 is etched and/or ion-milled to two depth. A rail surface 12 includes the top surface 14 of generally a channel shape. Thin film magnetic heads (transducers) 16 and 18 are embedded in the rail near at a trailing edge 51, with their pole facets being exposed. The rail surface 12 includes, in addition to the top surface 14, the shallow surface 20 and deep surface 22 at two-step depths milled down from the top surface 14. The shallow surface 20 extends from a leading edge 52 of the rail and milled to form a shallow step. The deep surface 22 constitutes the outer peripheral region of the rail and a negative pressure generating recess 24 surrounded by the rail having the top surface 14 of the channel shape, and is milled deeper than the shallow surface 20.
Upon rotation of a hard disk, air flowed from the leading edge 53 of the magnetic head 10 generates a positive pressure while passing along the shallow surface 20 and deep surface 22, and a negative pressure while passing along the negative pressure generating recess 24. The shallow surface 20, deep surface 22 and top surface 14 provide the function same as the taper surface of a magnetic head. The slider 11 maintains a constant flying height under a balanced condition of the positive and negative pressures.